1. Field of the Invention
The present invention relates to a touch device; in particular, to a touch device related to a push-button backlight technology.
2. Description of Related Art
As technologies improve, demands of home appliance for people in everyday life also increases. Thus, controlling interfaces in accordance with home appliance diversifies, too. For example, remote control devices for televisions and air conditioners, or control panels of washing machines and refrigerators.
FIG. 1 shows a cross-sectional diagram of a traditional touch device which can be disposed on the aforementioned remote control devices or control panels. In the traditional touch device 9, a light source 90 emits light into a light guiding plate 92, and the light is transmitted to a plurality of button icons 94 through the light guiding plate 92, such that the light can penetrate the surface of each button icon 94. On the other hand, underneath each button icon 94 is disposed with a touch sensor 96 for sensing whether the button icon 94 is touched by a user. When the touch sensor 96 senses that the button icon 94 is touched by the user, the touch sensor 96 can activate the function corresponding to the button icon 94.
However, as functionality of home appliance increases, indications on the touch device are more and more complex. As these touch icons functions in cooperation with a light guiding plate, these touch icons may not display independently or indicate one of these touch icons only, therefore readability of each touch icon is degraded. Also, in order to have each button icon emit light independently, a light is generally required to be disposed under each button icon, which is known as direct-type lighting design. However, direct-type lighting needs a set light blending distance so as to emit uniform light. The light blending distance may lead to difficulty in reducing the thickness of the touch device; meanwhile, sensitivity of the touch sensor may also be decreased.